The present invention relates to a video content transmitting system for transmitting video contents requested from a video content play terminal or video viewer terminal. More particularly, the present invention relates to a video content transmitting system having a plurality of video content servers using different video content transmitting network protocols, the video content transmitting system transmitting video contents to a plurality of video content play terminals using different video content receiving network protocols.
With recent high speed and broad bandwidth of the Internet and intranet, it becomes possible to transmit not only text data but also multimedia data such as audio and video data over networks. The International Organization for Standardization are making various standards of specifications to be used for communications over networks.
For example, the Internet Engineering Task Force (IETF) has standardized protocols to be used for communications over networks, such as HTTP (Hyper Text Transfer Protocol (RFC1945)), RTP (Real-time Transfer Protocol (RFC1889)), RSVP (ReSerVation Protocol (RFC2205)) and RTSP (Real Time Streaming Protocol (RFC2326)). Along with these developments, video content transmitting servers have been realized for transmitting video contents requested by video content play terminals to the terminals connected to the Internet, by using various standardized protocols.
For example, there are video on demand products such as RealVideo (Real Networks Corp.) and QuickTime3 (Apple Computer Inc.) both using HTTP and QuickTime4 (Apple Computer Inc.) using RTSP/RTP (Real Time Streaming Protocol/Real-time Transfer Protocol. Other types of video content transmitting servers have also been realized which can transmit high quality images of MPEG-2 to video content play terminals connected to a broader bandwidth network using ATM (Asynchronous Transfer Mode). For the details of such video content transmitting systems, refer to “Guide to Streaming Multimedia” (published by Wiley Computer Publishing Co.).
In a video content transmitting system having a plurality of video content transmitting servers for transmitting video contents by using various protocols, each video content play terminal receives desired video contents by using its network protocol in the following manner. First, the video content play terminal acquires beforehand information of video content transmitting servers capable of transmitting video contents by the protocol desired by the terminal. Then, the terminal directly accesses the desired server among those servers identified by the acquired video content transmitting server information. In this manner, the video content transmitting system can transmit the requested video contents to the terminal.